[SOLVED] Confirming that my PSU is dead

[Frazmitrater]

I'm 95% sure my PSU has died, but before I shell out for a new one I'd like a second opinion.
System:

• 600W Korean OEM ATX PSU (cabled, not modular, about 7 years old)
• MSI Z490 Unify MOBO (about 3 years old)
• System is a full tower with water cooling and plenty of ventilation

Symptoms:

• PC just quit without warning.
• No smells.
• Nothing working, not even PSU fan.
• Thought I might have overheated the CPU, but after 24 hours system still won't start. (No diagnostic beeps, no LED lights.)

Diagnostics thus far:

• I've tried the "paperclip" method - PSU fan does not spin.
• Replaced PSU fan with new one, still does not spin.
• Bought a cheap multi-meter. PIN voltages are mostly zero. Exceptions:

Pin 9 (5VSB) = +5.5C​

Pin 16 (PS-ON#) = 4V​

Can anyone think of anything else to test or try before buying a new PSU?
Many thanks in advance.

 

[NightHawkRMX]

PSU is failed, replace.

 

[Frazmitrater]

Thank you.